Adjustable socket for interchangeable lamps in a projector



l 0r I H. c. WELLMAN ADJUSTABLE SOCKET FOR lNTERCHANGEABLE LAMPS IN A PROJEcTOR Fi led Nov. 22, 1954' attorney Patented Sept. 10, 1935 PATENT OFFICE ADJUSTABLE SOCKET FOR INTERCHANGE- ABLE LAMPS IN A PROJECTOR Howard C. Wellman, Rochester, N. Y., assignorto Eastman Kodak Company, Rochester, N. Y., a corporation oi New York Application November 22, 1934, Serial No. 754,306

Claims.

This invention relates to photography and particularly to lamp sockets for projection apparatus.

It is an object of the invention to provide an 5 adjustable lamp socket which provides a universal mounting in which lamps of diilerent filament shapes and characteristics can be used so that the lamp filaments can always be positioned properly with respect to the optical system of .the projector. .It is a further object to provide an adjustable lamp socket which can be adjusted easily and definitely without removing the lamp chimney of the projector. Another object is to provide a lamp socket which provides means for definitely locating the vertical position of the lamp filaments with respect to the optical axisv of the projector.

Other objects will appear hereinafter from the following specification, the novel features being pointed out in the claims at the end thereof.

Incandescent lamps for projecting apparatus as now commonly manufactured have the filaments arranged in a series of short coils arranged vertically in parallelism in a single transverse plane. The spaces between the individual coils of the light are made about equal to the diameter of the coils themselves so that with a proper reflector system the images of the several filaments may be reflected into the spaces between the actual filaments. The light projected through the condensers is thus in eifect a spot of light equal to the width of the filaments and their intervening spaces and of substantially uniiormjector, but frequently it is found necessary to use a lamp whose filaments are of such a size and shape that the reflector and condenser system of the projector cannot handle them in the most efficient manner unless the plane of the filaments can beswung at an angle to the optical axis of the projector so that the space between the filaments along the optical axis is sufliciently reduced to insure the most eflicient reflection oi the filaments.

It has been common practice to have the base of the lamp equipped with various means for engaging with specially designed sockets for'positioning the lamp filaments in a plane transverse- 1y of the optical axis of the projector. but my invention goes further than this by providing a lamp socket in which lamps of difierent filament characteristics can be used and adjusted by the relatively unskilled operator to operate in the optical system of a projector in the most efiicient 5 manner.

The novel features that I consider characteristic of my invention are set forth with particularity in the appended claims. 1

The invention itself, however. both as to its 10 organization and its method of operation, together with additional objects and advantages thereof will best be understoodsfrom the following description of specific embodiments when read in connection with the accompanying draw- Figs. 3, 4, and 5 are diagrammatic plan views of the top of the lamp socket showing diiierent positions of the lamp filaments with respect to the optical axis. 7

Like characters and references refer to corresponding parts in the several views. 30 Briefly, the invention consists of a cylindrical shell in which a standard lamp socket for receiving a lamp is definitely and permanently fixed and which will be referred to throughout this specification as a socket. This socket is adjust- 35 ably confined by a clamping cylinder which has flanges on one end which serve as a base ,for mounting the assembled device in the lamphouse oi the projector. The clamping cylinder is provided on its upper rim with a notch which when 40 aligned with suitable markings on the surface of thesocket definitely positions the filaments oi the I lamp with respect to the optical axis of the projector. The lamp socket is held in position in the lamphouse by two bolts which are accessible from 45 the outside of the lamphouse, one of which acts through an :arcuate slot in the base of the lamphouse to provide a limited adjustment of the lamp socket as a whole while pivoting around the other bolt. The base of the clamping cylinder is 150 provided with a bracket which extends vertically downward parallel with the opening in the cylinder and which has a foot on one end extending into the mouth of the clamping cylinder to provide a base on which the socket is seated and thereby definitely position the lamp filaments vertically in the lamphouse. The lamp chimney is provided with openings which are aligned with the adjusting means of the socket so that all necessary adjustments of the lamp can be accomplished without removing the lamp chimney.

The reference character I designates the socket in which a lamp is positioned in a definite position by any well-known means. Socket I is adjustably confined by the clamping cylinder 2 in which the gripping tension is accomplished by an adjusting screw acting at l. The vertical position of the socket I is definitely determined by means of the bracket which is an integral part of the base 6 of the clamping cylinder 2 and which acts as a. base on which the socket I is seated. The base 6 of the clamping cylinder 2 is held in place on the lamphouse base I by means of a fitted bolt 8 and a bolt 9 which passes through an areuate slot III in the base of the lamphouse. The heads of the bolts 8 and 9 are accessible from the outside of the lamphouse, and a certain amount of adjustment of the lamp socket in the lamphouse maybe made by loosening these two bolts 8 and 9 and with bolt 3 acting as a pivot point the whole socket assembly may be swung in an are guided by the bolt 9 sliding in the arcuate slot ID. The desired angular adjustment of the lamp filaments is made by aligning a given mark-I2 on the'surface of the socket I with a notch II in the upper rim of the gripping cylinder 2.

Opening I3, I4, and I5 are made in the wall of the lamp chimney I6 to enable the necessary adjustments of the socket assembly to be made without having to remove the lamp chimney itself. The opening I3 permits the operator to loosen the gripping cylinder 2 to allow the socket I to be rotated The opening I4 allows the operator to view the notch II so that the proper mark I2'can be aligned therewith for any desired angular displacement of the lamp filaments, and the opening I5 is made in the wall of the lamp chimney I6 to permit that portion of the base 6 in which the bolt 9 is located to protrude and be movable through a distance governed by the arcuate slot III in the lamphouse base I.

Figs. 3, 4, and 5 show three difierent positions in which the lamp filaments can be placed, namely 90, 45, and 30 with relation to the optical axis, but it is evident that there may be any number of positions dependent upon the number of lamps having different filament characteristics that may be used. In Figs. 3, 4, and 5, F refers to the lamp filament while '0. A. indicates the optical axis of the projection system. In order to initially locate the indicating mark I2, in Fig. 2, on the surface of the socket I in a predetermined position for any given lamp, 8. given lamp of a certain filamenttype is placed in the standard socket I said socket being equipped with suitable means for definitely engaging any lamp having a standard base. The socket I is then revolved until the filament is properly positioned with relation to the optical system of the projector, and when this position is found the mark I2 is made on the surface of the socket I in line with the notch II. This sition may be at any angle whatever but it definitely locates the point where all lamps of this type filament should be placed for proper projection purposes. Marks for all possible type lamps could be made in this way as shown at 20 and 2|, said marks being made distinguishable by colors or other suitable means. Then when an operator wishes to use a lamp of certain filament characteristics he could find the necessary adjustment for it by means of a chart made by the manufacturers for this purpose.

To operate this device all the operator has to do 5 is insert the desired lamp in the socket I said socket and lamp base being inter-related so that the lamp is definitely positioned. Through the opening I3 in the lamp house the adjusting screw of the clamping cylinder 2 is loosened to permit 10 the socket I to be rotated. From a chart or calculation the correct positioning mark I2 is found for the type of lamp filament to be used and this mark I2 is then aligned with the notch II in the rim of the gripping cylinder 2 by sighting through the opening I4 in the wall of the lamp chimney IS. After this adjustment the gripping cylinder 2 is again tightened to hold the socket I in position and projection is ready. The vertical position of the filaments with relation to the optical axis of the projectoris always determined correctly by seating the socket I on the bracket 5, and only in rare cases would it be necessary to position the socket assembly as a whole in the lamphouse base by loosening the bolts 8 and I and with 8 as a pivot, swinging the whole socket assembly in an are guided by the sliding action of bolt 9 in the arcuate slot III provided in the base of the lamphouse for this purpose.

This adjustable lamp socket for interchange- 3 able lamps in projection has several advantages over similar devices. First, it provides a universal mounting in which lamps having difietent filament characteristics can be positioned easily, quickly, and accurately in order to give the correct filament position in relation to the optical axis of the projector. Secondly, it provides for the above adjustments in such a way that the lamp chimney does not have to be removed, and it also definitely locates the lamps in the projector so that their filaments are in correct vertical position with respect to the optical axis.

Although I have shown and described certain specific embodiments of my invention, I am fully aware that many modifications thereof are possible. My invention, therefore, is not to be restricted except in so far as is necessitated by the prior art and by the spirit of the appended claims.

4 What I claim and desire to secure by Letters Patent in the United States is:

1. In a projection apparatus, the combination with a lamp house, of a socket for positioning a lamp in the lamp house, a movable mount for the socket comprising a base member, a gripping cylinder carried thereby adapted to releasably hold the socket member against turning, means carried by the base for limiting the lamp vertically into'the base but permitting the turning movement thereof, and indicating means carried by the socket and base members adapted to be brought into co-operative relation to indicate the proper position for a definite type of lamp.

2. In a projection apparatus, the combination with a lamp house, of a socket for positioning a lamp in the lamp house, a mount for the socket comprising a base member adjustably mounted in the lamp house by set screws passing through arcuate slots in said lamp house base, a gripping cylinder carried by the base member adapted to releasably hold the socket member against tuming, means on the base member for limiting the vertical position of the socket into the base, and indicating means on the socket and base members adapted to be brought into cooperative relation for correctly positioning the filaments of the lamp with respect to the optical axis of the projector.

3. In a projection apparatus, the combination with a lamp house, of a socket for positioning a lamp in the lamp house, a movable mount for the socket comprising a base member, a gripping cylinder carried thereby adapted to releasably hold the socket member in any desired position, and indicating means on the socket and the gripping cylinder comprising predetermined marks on the socket and a notch in the rim of the gripping cylinder adapted to be brought into cooperative relation to indicate the proper angular position of the lamp filaments for a definite type of lamp.

4. In a projection apparatus, the combination with a lamp house, of an apertured lamp chimney therein, a movable mount for a lamp located inside of the chimney, and consisting of two parts, said two parts comprising a socket member and a base member, each movably mounted relative to the lamprhouse and relative to each other, means for holding the movably mounted tive relation to indicate when the lamp is properly 5 positioned.

5. In a projection apparatus, the combination with a lamp house, of a socket for positioning the lamp in the lamp house, an adjustable mount for the socket comprising a base member, a gripping 10 cylinder carried thereby to releasably hold the socket against turning, means carried by the base for limiting the vertical movement or the lamp into the base but permitting turning, indicating means carried by the base and the socket mem- 15 bars adapted to be brought into cooperative relation to indicate the proper position for a definite type of lamp and a lamp chimney enclosing the lamp and socket assembly said lamp chimney having suitable apertures for permitting all nec- 20 essary adjustments of the socket without necessitating the removal of the lamp chimney.

HOWARD C. WEILMAN. 

